High-fidelity simulation of flows in bone-like environment to investigate the growth of cancer cells

Metastatic cancer in bones is incurable, which causes significant mobility and mortality to the patients. In this work, we investigate the role of interstitial fluid flow on cancer cells' growth within the interconnected pores of human bone. In-vitro experiments were carried out in a bio-reactor which includes bone-like scaffold specimens. A pump is used to maintain a laminar flow condition inside the bioreactor to resemble fluid flow in bones. The scaffold specimens are harvested after 23 days in the bioreactor. The scaffold specimen is scanned with Micro-CT under the resolution of 70 micrometers. We created a full-scale 3D computational model of the scaffold based on the micro-CT data using the open-source software Seg3D and Meshmixer. Based on the geometrical models, we generated the computational grids using the commercial software Gridgen. We performed Computational Fluid Dynamics (CFD) simulations with the immersed boundary method (Gilmanov, Le, Sotiropoulos, JCP 300, 1, 2015) to investigate the flow patterns inside the pores of the scaffolds. The results reveal a nonuniform flow distribution in the vicinity of the scaffold. The flow velocity and the shear stress distributions inside the scaffold are shown to be convoluted and very sensitive to the pore sizes. Our future work will further quantify these distributions and correlate them to cancer cells' growth observed in the experiments.